Trump 2nd term live updates: Dan Bongino named as deputy FBI director

Secretary of State Marco Rubio arrived in Saudi Arabia on Monday ahead of expected U.S.-Russia talks there on ending Moscow's war on Ukraine, though Kyiv's representatives are not expected to take part.

Rubio will be joined by Middle East envoy Steve Witkoff and National Security Adviser Mike Waltz.

Kremlin spokesperson Dmitry Peskov told reporters on Monday that the Russian delegation would include Foreign Minister Sergei Lavrov, President Vladimir Putin's aide Yuri Ushakov and Kirill Dmitriev -- the head of Russia's sovereign wealth fund.

"On Tuesday in Riyadh they will hold a meeting with American counterparts, which will be devoted, first of all, to restoring the entire range of Russian-American relations," Peskov said. The teams will also discuss a potential in-person meeting between Putin and President Donald Trump, Peskov said.

Ukraine is not expected to be represented in the coming round of talks, despite calls from Kyiv and across Europe for President Volodymyr Zelenskyy and his team to play a role.

-ABC News' Joe Simonetti

President Donald Trump's administration acknowledged on Sunday night that some federal government employees who took the "Fork in the Road" buyout offer were also, subsequently, fired or let go — and that this was an error.

An Office of Personnel Management official told ABC News that some employees who responded to the buyout offer ahead of the deadline last week may have received termination notices by mistake but, for those personnel, the buyouts agreements would be honored.

Nick Detter told ABC News that he is one of those workers. Detter, a natural resource specialist with the USDA, said he was fired Thursday even though he already accepted the administration's buyout offer, meaning that he should have been paid through September.

Despite OPM’s explanation, Detter says he hasn’t been able to get any guidance directly. He said that his supervisors in Kansas, where he’s based, told him they have no information.

"I frankly find it pretty insulting and chaotic and disorganized," Detter told ABC News.

"I would never say that there's no room for improvement efficiency in the federal government," he said. "But in my experience over the last month with this whole thing, that's not what this has been. This has just been slash and burn."

-ABC News' Rachel Scott, Cheyenne Haslett, Sarah Lang and Ariana Nalty

Elon Musk’s Department of Government Efficiency has requested access to an IRS data system that retains the personal tax information on millions of Americans, two sources familiar with the matter told ABC News.

The system, known as the Integrated Data Retrieval System, or IDRS, is used by IRS employees to review tax information, issue notices to taxpayers and update taxpayer records.

Access to the data, which is tightly controlled within the agency, had not been granted as of this weekend, several sources told ABC News.

-ABC News' Anne Flaherty, Soo Youn, Benjamin Siegel, Olivia Rubin and Hannah Demissie